After living in isolation for 60,000 years, only 38 desert fish are still alive today, how did the fish survive in the arid desert, why can't they be transferred outside the desert, and then artificially build a suitable living environment to protect them.
Death Valley in California, USA, is a large desert with a strange little fish that have survived wind, sand and drought for more than 60,000 years. As we all know, fish can't survive for too long without water, so why do these desert fish survive in the desert where water is scarce? In fact, the desert is not completely dry, and these desert fish do not live directly in the sand, but stay in a small pool in the desert.
The fish lives in Death Valley, the lowest, driest and hottest part of North America, between the Mojave and Colorado deserts, on the state border between California and Nevada, where summer temperatures reach 56 degrees Celsius and the air contains almost zero moisture. There is a Devil's Cave in Death Valley, an oasis in the desert, and there is an underground water in the Devil's Cave, where the water temperature is maintained at 33 degrees Celsius all year round, which can be regarded as relatively cool compared to the hot weather outside. The cave is 22 meters long and 3.5 meters wide, with a maximum depth of about 130 meters, and its unique environment breeds a unique group of desert fish. The desert fish, also known as the medaka, is a rare fish species, its body length is no more than 3cm, and it is a unique species of the devil's cave.
The small fish that live in the desert, how did they come here, and why they have not become extinct after 60,000 years.
Death Valley National Park is a vast area with a total length of 225 kilometers, 26 kilometers at its widest point and about 6 kilometers at its narrowest point, covering an area of 1,408 square kilometers. The valley is deserted and has no rivers, and has been the site of many explorers and gold prospectors, hence the name Death Valley, which is how the desert fish found water to survive. In fact, tens of thousands of years ago, it was not a place of yellow sand, but a lush wetland and lake. Surrounded on all sides by Mount Nevada, Mount Parami and Mount Agas, Ice Age water poured into the valley, and abundant rainfall created a salt lake and wetland where the ancestors of desert fish migrated some 60,000 years ago and have lived here ever since.
With climate change and geological movements, the water level of the salt lake has dropped, the water flow has gradually dried up, the lack of water has caused a large number of plants to die, animals have no food source, and soon disappear, and the place slowly turns into an endless desert, leaving only the deepest Devil's Cave and a group of small fish that live here. The small habitat makes them have to work harder to survive, and they can only learn to adapt to the harsh environment of the desert when they can't leave, and the manta fish has been shrinking in size during the evolutionary process, from the normal size at the beginning to about 3 centimeters now, which looks like a severe stunt.
Desert fish live in a very harsh environment, so why not move them all outside and build a suitable protected area?
Since the discovery of desert fish, its population has not exceeded 500, the habitat of the Devil's Cave is too small, it can not cope with the changing desert environment, other species can reproduce by migrating, but the desert fish can not leave the Devil's Cave at all, can only find a way to survive here. In order to save these endangered small fish, scientists came up with many methods, they built barbed wire outside the Devil's Cave and fed the desert fish, and within a few years the desert fish population ushered in a large increase. At this time, scientists thought about whether it was possible to move desert fish outside and increase their populations again. It's a good idea, but it's a lot of problems in practice.
After leaving the Devil's Cave, their spawning and hatching rate were extremely low, and the small fish they gave birth to did not live long, and after a few years of tossing, only a few dozen small fish were bred in the laboratory. And with the growth of time, these desert fish have mutated, not at all look like the original desert fish, scientists call this phenomenon phenotypic plasticity, an ability to make significant changes according to the external environment and conditions, which is contrary to genetics, but desert fish have this "superpower", scientists spent several years to finally build a water area close to the conditions of the devil's cave, and finally succeeded in breeding desert fish.